Coaling installation for power plants

ABSTRACT

Coaling installation for power plants includes a single coal supply bin, a plurality of coal crushers, coal feeding means for the crushers, respective chutes sealingly connected at one end to the coal feeding means, endless conveyor means for conveying from supply bin to distribute coal in excess of the capacity of the crushers, the conveyor means being formed with discharge openings and overlying the other end of the chutes so that the openings are alignable with the chutes for discharging therethrough into the crushers a quantity of coal substantially equal to crusher capacity, and additional means for conveying excess coal remaining on the endless conveyor means to a coal dump.

United States Patent [1 1 Maier et al.

COALING INSTALLATION FOR POWER PLANTS inventors: Eberhard Maier; WalterEndler,

both of Erlangen; Paul Haack, Erlangen-Buchenbach, all of GermanyAssigneez Siemens Aktiengesellschaft,

Berlin/ Munich, Germany Filed: Sept. 15, 1971 Appl. No.: 180,859

Related US. Application Data Continuation of Ser. No. 834,619, June 18,1969, abandoned.

Foreign Application Priority Data References Cited UNITED STATES PATENTSDavis 198/66 X [4 1 Nov. 6, 1973 Primary Examiner-Granville Y. Custer,Jr. Att0rneyArthur E. Wilfond et al.

[57] ABSTRACT Coaling installation for power plants includes a singlecoal supply bin, a plurality of coal crushers, coal feeding means forthe crushers, respective chutes sealingly connected at one end to thecoal feeding means, endless: conveyor means for conveying from supplybin to distribute coal in excess of the capacity of the crushers, theconveyor means being formed with discharge openings and overlying theother end of the chutes so that the openings are alignable with, thechutes for discharging therethrough into the Crushers a quantity of coalsubstantially equal to crusher capacity, and additional means forconveying excess coal remaining on the endless conveyor means to a coaldump.

PATENTEB NUY 6l975 COALING INSTALLATION FOR POWER PLANTS This is acontinuation of application Ser. No. 834,619, filed June 18, 1969, nowabandoned.

Our invention relates to coaling installation for power plants.

It has been conventional heretofore, in the case of steam power plants,for.example, that are heated by coal, to provide for the required coalcrushers a separate coal bin or bunker of heavy construction whichgenerally determines the size of the boiler house. Thisheavy-constructed bunker has proven to be very costly however, in termsof money, construction time and materials, since a specific quantity ofcoal must always be kept available for the individual coal crushers.

It is accordingly an object of our invention to provide coalinginstallation for power plants which avoids the foregoing shortcomings ofthe heretofore known coaling installations of this general type.

More particularly, it is an object of our invention to provide suchcoaling installation which entirely dispenses with a heavy-constructedbunker or steel bin in the boiler house and in which the'coal crushersare supplied only with a given required quantity of coal respectively.

Moreover, it is another object of our invention to provide such coalinginstallation with a supply bin generally constructed as an undergroundbunker so as to avoid any necessity for serially interconnecting a pairof working tanks.

With the foregoing and other objects in view, we provide in accordancewith our invention, coaling installation for power plants comprising asingle coal supply bin, a plurality of coal crushers, crusher feedingmeans connected at one end to the coal crushers respectively, chutemeans sealingly connected at one end thereof to the other end of thecrusher feeding means, endless conveyor means extending from the coalsupply bin to the crusher feeding means for conveying thereto coal inexcess of the capacity of the plurality of coal crushers, the conveyormeans being formed with discharge openings and overlying the other endof the chute means so that the discharge openings are alignable with thechute means for discharging therethrough and through the crusher feedingmeans to the coal crushers a quantity of coal substantially equal to thecapacity of the coal crushers, and additional conveyor means forconveying excess coal remaining on the endless conveyor means to a coaldump. Accordingly, only so much coal is supplied by the endless conveyormeans, such as bucket chain conveyors, to each coal crusher that thechutes are substantially evenly filled.

In accordance with another feature of our invention, and in order toprovide an uninterrupted supply of coal to the coal crushers, theendless conveyor means is made up of two bucket chain conveyorsextending parallel to one another.

In accordance with additional features of our invention, the supply binis constructed as an underground supply bunker, and the endless conveyormeans comprises a first length thereof extending at an upward slope fromthe underground supply bunker to a level overlying the coal chutes, anda second length substantially intersecting the first length andextending substantislly horizontally above the coal chutes.

In accordance with a further feature of our invention, the additionalconveyor means for conveying excess coal from the endless conveyor meansto a coal dump comprises a single endless conveyor that is at leastpartly pivotable.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin coaling installation for power plants, it is nevertheless notintended to be limited to the details shown, since various modificationsand structural changes may be made therein without departing from thespirit of the invention and with the scope and range of equivalents ofthe claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying single FIG- URE of the drawingin which there is presented in perspective and diagrammatic view anembodiment of a coaling installation constructed in accordance with ourinvention. I

Referring now to the drawing, there is shown a supply bin 1, in the formof an underground discharge bunker, to which coal is delivered byconventional transporting means such as the illustrated rail cars. Theunderground bunker 1 has a volumetric capacity that is ade-, quate forsupplying a full load of coal to the coal crushers 7 for a given numberof hours. The coal is conveyed from the underground bin 1 bybin-discharge carriages 2 and clodcrushers 3 to a pair ofparallel-extending, inclined conveyors 4, preferably in the form ofbucket chain conveyors. The inclined conveyors 4 transport the coalinitially to a level above the upper end of thecoal distributors 8,which are connected at the other ends thereof, respectively, to the coalcrushers 7. The

coal is dropped from the upper end of the inclined conveyors 4 onto apair of parallel substantially horizontally extending bucket chainconveyors 6. The individual coal crushers 7, as can be seen in theFIGURE, are connected through respective crusher feeders 8, such asconventional conveyor belts, and chutes 9 with the horizontal bucketchain conveyors 6. In the vicinity of each of the chutes 9, the bucketchain conveyors 6 are formed on the underside thereof with dischargeopenings 15 through which the chutes 9 are supplied with coal. Thequantity of coal that is not dropped into the first chutes 9 passed bythe bucket chain conveyors 6 i.e. those chutes 9 connected through therespective feeders 8 to the coal crushers 7 shown at the most lefthandlocation in the FIGURE, is further conveyed by the conveyors 6 to thechutes 9 of the respective coal crushers 7 located farther downstreamfrom the first chutes. The coal excess necessarily remaining on theconveyors 6 is transferred at a transfer station 10located downstream ofthe chutes 9 to another conveyor 11 which conveys the coal excess backto a coal dump or storage space 14. Advantageously, at least the mostdownstream conveyor portion 12 is pivotable about a substantiallyvertical axis at a transfer station 13, so that the excessive quantityof coal can be suitably distributed at the coal dump 14 in the closestpossible proximity to the underground supply bunker 1. As shown in theFIGURE, the transfer station 13 is located in a tower similar to thosein which the transfer stations 5 and 10 are located, and beingsubstantially at the intersection of a fixed conveyor portion 11 and thepivotable conveyor portion.

For the purpose of providing an uninterrupted supply of coal to the coalcrushers 7, the bucket chain conveyors 4 and 6 are respectively providedin parallel pairs leading to respective pairs of chutes 9 for theindividual coal crushers 7, each of the conveyors of the pairs ofconveyors 4 and 6, being designed respectively to convey 100 percent ofthe load to the crushers 7. Thus, if one conveyor of each of the pairsof conveyors 4 and 6 were to break down, then the other conveyor of thatpair would still be able to convey an adequate 100 percent supply ofcoal to the coal crushers 7. The return or recovery conveyor 1 1, forconveying the excess coal back to the coal dump 14, on the other hand,can be of simpler construction than the double conveyors 4 and 6, sincea breakdown of the recovery conveyor 11, an emergency release can beprovided at or just downstream of the transfer station 10, which can beserviced for example, by a motor truck i.e., a dump truck can be backedup to the rear side of the tower at transfer station 10, as viewed inthe FIGURE, so that any excess coal being advanced on the conveyors 6will then drop from that tower directly onto the dump truck.

Since the coal crushers 7, which are of conventional construction,generally operate under excess pressure, the necessary sealing thereofagainst the outer atmosphere is provided by the chutes 7 which areconstantly filled with coal.

The coaling installation of our invention permits the costly bunker ofheavy construction or steel in the boiler house to be dispensed with,without endangering the uninterrupted supply of the required quantity ofcoal to the coal crushers. Even when the bucket chain conveyors 6 areswitched on and off, the content of the chutes 9 ensure uninterruptedsupply of the coal crushers 7.

Due to the fact that the conveyors 4 and 6 are in duplicate, one of theduplicates of each pair of conveyors can be employed witut anyadditional measures for spot-coaling.

The coaling installation of our invention can not only be employed forsteam power plants but also for other plants which require uniformdistribution of solid fuels.

We claim:

1. Coaling installation for power plants comprising an undergroundsupply bunker defining a single coal supply bin, a plurality of coalcrushers, crusher feeding means connected at one end to said coalcrushers respectively, chute means connected at one end thereof to theother end of said crusher feeding means, endless conveyor meanscomprising a first portion thereof extending at an upward slope fromsaid underground supply bunker to a level overlying said coal chutes,and a second portion thereof substantially intersecting said firstportion and extending substantially horizontally above said coal chutes,said endless conveyor means conveying coal directly to said crusherfeeding means from said underground bunker in excess of the capacity ofsaid plurality of coal crushers, said second portion of said conveyormeans being formed with discharge openings overlying the other end ofsaid chute means so that said discharge openings are alignable with saidchute means for discharging therethrough and through i said crusherfeeding means to said coal crusher a quantity of coal substantiallyequal to the capacity of said coal crushers and for filling said chuteswith coal so as to seal said coal crushers against the outer atmosphere,and additional conveyor means for conveying excess coal remaining onsaid second portion of said endless conveyor means to a coal stockpiledownstream of said coal crushers in said direction of feed of the coaland at the very end of said conveyor system in said feed direction.

2. Coaling installation according to claim 1 wherein said additionalconveyor means comprises a single endless conveyor having at least onepart pivotable relative to the other part thereof.

l l l 4'

1. Coaling installation for power plants comprising an undergroundsupply bunker defining a single coal supply bin, a plurality of coalcrushers, crusher feeding means connected at one end to said coalcrushers respectively, chute means connected at one end thereof to theother end of said crusher feeding means, endless conveyor meanscomprising a first portion thereof extending at an upward slope fromsaid underground supply bunker to a level overlying said coal chutes,and a second portion thereof substantially intersecting said firstportion and extending substantially horizontally above said coal chutes,said endless conveyor means conveying coal directly to said crusherfeeding means from said underground bunker in excess of the capacity ofsaid plurality of coal crushers, said second portion of said conveyormeans being formed with discharge openings overlying the other end ofsaid chute means so that said discharge openings are alignable with saidchute means for discharging therethrough and through said crusherfeeding means to said coal crusher a quantity of coal substantiallyequal to the capacity of said coal crushers and for filling said chuteswith coal so as to seal said coal crushers against the outer atmosphere,and additional conveyor means for conveying excess coal remaining onsaid second portion of said endless conveyor means to a coal stockpiledownstream of said coal crushers in said direction of feed of the coaland at the very end of said conveyoR system in said feed direction. 2.Coaling installation according to claim 1 wherein said additionalconveyor means comprises a single endless conveyor having at least onepart pivotable relative to the other part thereof.